Bioquell can trace its roots more than 200 years and, in an earlier guise, helped install the plumbing at Balmoral Castle.

More recently, it has developed products to curb and kill bacteria and initially deployed this expertise in the defence industry, designing equipment to protect soldiers against chemical and biological weapons.

Its technology was considered so pioneering that it was adopted by the US Department of Defense and is now used by armies worldwide.

Over the past decade, Bioquell has adapted its technology for hospitals and drugs producers.

The group is expected to deliver profits up five per cent at £5.2 million this year, rising to at least £5.6 million in 2013. It is forecast to pay a dividend of 3.1p for 2012, against 2.62p last year.

Bioquell is poised to make substantial progress over the next few years and the shares should rise. Buy.